Re: [PATCH] tty: increase the default flip buffer limit to 2*640K

From: Greg KH
Date: Mon Jan 28 2019 - 11:53:26 EST


On Mon, Jan 28, 2019 at 05:38:43PM +0100, Martin Kepplinger wrote:
> From: Manfred Schlaegl <manfred.schlaegl@xxxxxxxxxxxxx>
>
> The default value for this was 64K. We increase this by a factor of
> 10 to 640K to prevent data loss when using fast serial interfaces.

What fast serial interface are you using where you run into this limit?

> Since this value is only a maximum limit for allocation and isn't used
> by default, this change has minimal effect on systems with slow interfaces.

So what systems does it affect?

> Signed-off-by: Manfred Schlaegl <manfred.schlaegl@xxxxxxxxxxxxx>
> Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxxxxxxxx>
> ---
>
> Is there any reason for this _limit_ to be as small as 64K?

Historical mostly from what I can tell.

thanks,

greg k-h